Android ORM框架介绍之greenDao封装(二)

Android ORM框架介绍之greenDao封装(二)

数据库操作增删改查操作重复太高，所以需要进行抽取，通过DataBaseManager统一管理。

package www.weshared.greendao;

import android.content.Context;
import android.database.Cursor;
import android.support.annotation.NonNull;
import com.zhang.db.dao.DaoMaster;
import com.zhang.db.dao.DaoSession;
import com.zhang.db.entity.BaseModel;
import com.zhang.db.entity.Model;
import org.greenrobot.greendao.AbstractDao;
import org.greenrobot.greendao.query.WhereCondition;
import java.util.List;

public class DataBaseManager {

    protected static final String DB_NAME = "my.db";
    protected final DaoSession session;
    protected final AbstractDao dao;

    private static final String DB_NAME = "my.db";
    private DaoSession session;
    private AbstractDao dao;
    private DaoMaster.DevOpenHelper helper;
    private DaoMaster master;

    private static volatile DataBaseManager manager;

    private DataBaseManager(Context context) {
        if (helper == null) {
            helper = new DaoMaster.DevOpenHelper(context, DB_NAME);
        }
    }

    public static DataBaseManager getInstance(Context context) {
        if (manager == null) {
            synchronized (DataBaseManager.class) {
                if (manager == null) {
                    manager = new DataBaseManager(context);
                }
            }
        }
        return manager;
    }

    //未加密
    public DataBaseManager create(T t) {
        if (helper != null) {
            master = new DaoMaster(helper.getWritableDb());
        }
        session = master.newSession();
        dao = createDao(session, t.getClass());
        return manager;
    }

    //加密  [需要依赖 compile 'net.zetetic:android-database-sqlcipher:3.5.3']
    public DataBaseManager create(String pwd,T t) {
        if (helper != null) {
            master = new DaoMaster(helper.getEncryptedWritableDb(pwd));
        }
        session = master.newSession();
        dao = createDao(session, t.getClass());
        return manager;
    }
    //如果Model类太多，使用工厂模式
    public AbstractDao createDao(@NonNull DaoSession session, Class clazz) {
        if (BaseModel.class.equals(clazz)) {
            return session.getBaseDao();
        } else if (Model.class.equals(clazz)) {
            return session.getModelDao();
        }
        return null;
    }

    public long insert(T t) {
        return session.insert(t);
    }

    public long insertOrReplace(T t) {
        return session.insertOrReplace(t);
    }

    @SuppressWarnings("unchecked")
    public void insertAll(List list) {
        dao.insertInTx(list);
    }

    @SuppressWarnings("unchecked")
    public void insertOrReplaceAll(List list) {
        dao.insertOrReplaceInTx(list);
    }

    public void update(T t) {
        session.update(t);
    }

    @SuppressWarnings("unchecked")
    public void updateAll(List list) {
        dao.updateInTx(list);
    }

    public void delete(T t) {
        session.delete(t);
    }

    @SuppressWarnings("unchecked")
    public void deleteAll(List list) {
        dao.deleteInTx(list);
    }

    public void deleteAll() {
        dao.deleteAll();
    }

    @SuppressWarnings("unchecked")
    public List queryAll() {
        return dao.loadAll();
    }

    @SuppressWarnings("unchecked")
    public T query(long id) {
        return (T) dao.loadByRowId(id);
    }

    @SuppressWarnings("unchecked")
    public T query(Object key) {
        return (T) dao.load(key);
    }

    /**
     * 简单的条件查询
     */
    @SuppressWarnings("unchecked")
    public List query(String where, String... args) {
        return dao.queryRaw(where, args);
    }

    /**
     * 简单的条件查询
     */
    @SuppressWarnings("unchecked")
    public List queryBuild1(WhereCondition condition, WhereCondition... conditions) {
        return dao.queryBuilder().where(condition, conditions).build().list();
    }

    /**
     * 查询个数
     */
    @SuppressWarnings("unchecked")
    public long queryBuild2(WhereCondition condition, WhereCondition... conditions) {
        return dao.queryBuilder().where(condition, conditions).buildCount().count();
    }

    /**
     * 获取Cursor
     */
    @SuppressWarnings("unchecked")
    public Cursor queryBuild3(WhereCondition condition, WhereCondition... conditions) {
        return dao.queryBuilder().where(condition, conditions).buildCursor().query();
    }

}

工厂模式抽取[注：如果类太多，使用工厂方法模式]

public class DaoFactory {

    public static AbstractDao createDao(@NonNull DaoSession session, Class clazz) {
        if (BaseModel.class.equals(clazz)) {
            return session.getBaseDao();
        } else if (Model.class.equals(clazz)) {
            return session.getModelDao();
        }
        return null;
    }
}

在MainActivity中的使用

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

    private Button insert;
    private Button delete;
    private Button deleteall;
    private Button update;
    private Button query;
    private Button queryall;
    private Button querybuild;
    private TextView tv_query;
    private TextView tv_queryall;
    private TextView tv_querybuild;
    private DataBaseManager manager;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        init();
        initView();
        initListener();
    }

    private void init() {
        try {
            manager = new DataBaseManager(MainActivity.this, Model.class.newInstance());
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    private void initView() {
        insert = (Button) findViewById(R.id.btn_insert);
        delete = (Button) findViewById(R.id.btn_delete);
        deleteall = (Button) findViewById(R.id.btn_deleteall);
        update = (Button) findViewById(R.id.btn_update);
        query = (Button) findViewById(R.id.btn_query);
        queryall = (Button) findViewById(R.id.btn_queryall);
        querybuild = (Button) findViewById(R.id.btn_querybuild);

        tv_query = (TextView) findViewById(R.id.tv_query);
        tv_queryall = (TextView) findViewById(R.id.tv_queryall);
        tv_querybuild = (TextView) findViewById(R.id.tv_querybuild);
    }

    private void initListener() {
        insert.setOnClickListener(this);
        delete.setOnClickListener(this);
        deleteall.setOnClickListener(this);
        update.setOnClickListener(this);
        query.setOnClickListener(this);
        queryall.setOnClickListener(this);
        querybuild.setOnClickListener(this);
    }

    @Override
    public void onClick(View view) {
        switch (view.getId()) {
            case R.id.btn_insert:
                Model model = new Model();
                model.setName("zhangsan");
                model.setAge(32);
                model.setCreateTime(System.currentTimeMillis());
                manager.insert(model);
                break;
            case R.id.btn_update:
                Model model1 = new Model();
                model1.setId((long) 1);
                model1.setName("lisi");
                model1.setAge(23);
                model1.setCreateTime(System.currentTimeMillis());
                manager.update(model1);
                break;
            case R.id.btn_delete:
                Model model2 = new Model();
                model2.setId((long) 2);
                manager.delete(model2);
                break;
            case R.id.btn_deleteall:
                manager.deleteAll();
                break;
            case R.id.btn_query:
                Model m = manager.query(1);
                if (m!=null){
                    tv_query.setText("单条查询："+m.toString());
                }else {
                    tv_query.setText("单条查询：没有查询到结果");
                }
                break;
            case R.id.btn_queryall:
                List li = manager.queryAll();
                tv_queryall.setText("查询全部："+li.toString());
                break;
            case R.id.btn_querybuild:
                List list = manager.queryBuild1(ModelDao.Properties.Name.like("zhangsan"));//注意条件查询
                tv_querybuild.setText("条件查询："+list.toString());
                break;
        }
    }
}

水平有限，封装的不是很好